/* SPDX-License-Identifier: GPL-2.0 */
/*
 * NOTE:
 *
 * This header has combined a lot of unrelated to each other stuff.
 * The process of splitting its content is in progress while keeping
 * backward compatibility. That's why it's highly recommended NOT to
 * include this header inside another header file, especially under
 * generic or architectural include/ directory.
 */
#ifndef _LINUX_KERNEL_H
#define _LINUX_KERNEL_H

// #include <linux/stdarg.h>
// #include <linux/align.h>
// #include <linux/limits.h>
// #include <linux/linkage.h>
// #include <linux/stddef.h>
#include <linux/compiler.h>
#include <linux/types.h>
#include <stdbool.h>
// #include <linux/container_of.h>
// #include <linux/bitops.h>
// #include <linux/kstrtox.h>
// #include <linux/log2.h>
// #include <linux/math.h>
// #include <linux/minmax.h>
// #include <linux/typecheck.h>
// #include <linux/panic.h>
// #include <linux/printk.h>
// #include <linux/build_bug.h>
// #include <linux/static_call_types.h>
// #include <linux/instruction_pointer.h>
// #include <asm/byteorder.h>
#include <stdarg.h>

// #include <uapi/linux/kernel.h>

#define STACK_MAGIC 0xdeadbeef

/**
 * REPEAT_BYTE - repeat the value @x multiple times as an unsigned long value
 * @x: value to repeat
 *
 * NOTE: @x is not checked for > 0xff; larger values produce odd results.
 */
#define REPEAT_BYTE(x) ((~0ul / 0xff) * (x))

/* generic data direction definitions */
#define READ 0
#define WRITE 1

/**
 * ARRAY_SIZE - get the number of elements in array @arr
 * @arr: array to be sized
 */
#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))

#define PTR_IF(cond, ptr) ((cond) ? (ptr) : NULL)

#define u64_to_user_ptr(x)             \
    ({                                 \
        typecheck(u64, (x));           \
        (void __user *)(uintptr_t)(x); \
    })

/**
 * upper_32_bits - return bits 32-63 of a number
 * @n: the number we're accessing
 *
 * A basic shift-right of a 64- or 32-bit quantity.  Use this to suppress
 * the "right shift count >= width of type" warning when that quantity is
 * 32-bits.
 */
#define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))

/**
 * lower_32_bits - return bits 0-31 of a number
 * @n: the number we're accessing
 */
#define lower_32_bits(n) ((u32)((n) & 0xffffffff))

/**
 * upper_16_bits - return bits 16-31 of a number
 * @n: the number we're accessing
 */
#define upper_16_bits(n) ((u16)((n) >> 16))

/**
 * lower_16_bits - return bits 0-15 of a number
 * @n: the number we're accessing
 */
#define lower_16_bits(n) ((u16)((n) & 0xffff))

struct completion;
struct user;

#ifdef CONFIG_PREEMPT_VOLUNTARY_BUILD

extern int __cond_resched(void);
#define might_resched() __cond_resched()

#elif defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_CALL)

extern int __cond_resched(void);

DECLARE_STATIC_CALL(might_resched, __cond_resched);

static __always_inline void might_resched(void) { static_call_mod(might_resched)(); }

#elif defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_KEY)

extern int dynamic_might_resched(void);
#define might_resched() dynamic_might_resched()

#else

#define might_resched() \
    do {                \
    } while (0)

#endif /* CONFIG_PREEMPT_* */

#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
extern void __might_resched(const char *file, int line, unsigned int offsets);
extern void __might_sleep(const char *file, int line);
extern void __cant_sleep(const char *file, int line, int preempt_offset);
extern void __cant_migrate(const char *file, int line);

/**
 * might_sleep - annotation for functions that can sleep
 *
 * this macro will print a stack trace if it is executed in an atomic
 * context (spinlock, irq-handler, ...). Additional sections where blocking is
 * not allowed can be annotated with non_block_start() and non_block_end()
 * pairs.
 *
 * This is a useful debugging help to be able to catch problems early and not
 * be bitten later when the calling function happens to sleep when it is not
 * supposed to.
 */
#define might_sleep()                      \
    do {                                   \
        __might_sleep(__FILE__, __LINE__); \
        might_resched();                   \
    } while (0)
/**
 * cant_sleep - annotation for functions that cannot sleep
 *
 * this macro will print a stack trace if it is executed with preemption enabled
 */
#define cant_sleep()                         \
    do {                                     \
        __cant_sleep(__FILE__, __LINE__, 0); \
    } while (0)
#define sched_annotate_sleep() (current->task_state_change = 0)

/**
 * cant_migrate - annotation for functions that cannot migrate
 *
 * Will print a stack trace if executed in code which is migratable
 */
#define cant_migrate()                                                  \
    do {                                                                \
        if (IS_ENABLED(CONFIG_SMP)) __cant_migrate(__FILE__, __LINE__); \
    } while (0)

/**
 * non_block_start - annotate the start of section where sleeping is prohibited
 *
 * This is on behalf of the oom reaper, specifically when it is calling the mmu
 * notifiers. The problem is that if the notifier were to block on, for example,
 * mutex_lock() and if the process which holds that mutex were to perform a
 * sleeping memory allocation, the oom reaper is now blocked on completion of
 * that memory allocation. Other blocking calls like wait_event() pose similar
 * issues.
 */
#define non_block_start() (current->non_block_count++)
/**
 * non_block_end - annotate the end of section where sleeping is prohibited
 *
 * Closes a section opened by non_block_start().
 */
#define non_block_end() WARN_ON(current->non_block_count-- == 0)
#else
static inline void __might_resched(const char *file, int line, unsigned int offsets) {}
static inline void __might_sleep(const char *file, int line) {}
#define might_sleep()    \
    do {                 \
        might_resched(); \
    } while (0)
#define cant_sleep() \
    do {             \
    } while (0)
#define cant_migrate() \
    do {               \
    } while (0)
#define sched_annotate_sleep() \
    do {                       \
    } while (0)
#define non_block_start() \
    do {                  \
    } while (0)
#define non_block_end() \
    do {                \
    } while (0)
#endif

#define might_sleep_if(cond)     \
    do {                         \
        if (cond) might_sleep(); \
    } while (0)

#if defined(CONFIG_MMU) && (defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_DEBUG_ATOMIC_SLEEP))
#define might_fault() __might_fault(__FILE__, __LINE__)
void __might_fault(const char *file, int line);
#else
static inline void might_fault(void) {}
#endif

extern int no_hash_pointers_enable(char *str);

extern int get_option(char **str, int *pint);
extern char *get_options(const char *str, int nints, int *ints);
extern unsigned long long memparse(const char *ptr, char **retptr);
extern bool parse_option_str(const char *str, const char *option);
extern char *next_arg(char *args, char **param, char **val);

extern int core_kernel_text(unsigned long addr);
extern int __kernel_text_address(unsigned long addr);
extern int kernel_text_address(unsigned long addr);
extern int func_ptr_is_kernel_text(void *ptr);

extern void bust_spinlocks(int yes);

extern int root_mountflags;

extern bool early_boot_irqs_disabled;

/*
 * Values used for system_state. Ordering of the states must not be changed
 * as code checks for <, <=, >, >= STATE.
 */
extern enum system_states {
    SYSTEM_BOOTING,
    SYSTEM_SCHEDULING,
    SYSTEM_FREEING_INITMEM,
    SYSTEM_RUNNING,
    SYSTEM_HALT,
    SYSTEM_POWER_OFF,
    SYSTEM_RESTART,
    SYSTEM_SUSPEND,
} system_state;

extern const char hex_asc[];
#define hex_asc_lo(x) hex_asc[((x) & 0x0f)]
#define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4]

static inline char *hex_byte_pack(char *buf, u8 byte) {
    *buf++ = hex_asc_hi(byte);
    *buf++ = hex_asc_lo(byte);
    return buf;
}

extern const char hex_asc_upper[];
#define hex_asc_upper_lo(x) hex_asc_upper[((x) & 0x0f)]
#define hex_asc_upper_hi(x) hex_asc_upper[((x) & 0xf0) >> 4]

static inline char *hex_byte_pack_upper(char *buf, u8 byte) {
    *buf++ = hex_asc_upper_hi(byte);
    *buf++ = hex_asc_upper_lo(byte);
    return buf;
}

bool mac_pton(const char *s, u8 *mac);

/*
 * General tracing related utility functions - trace_printk(),
 * tracing_on/tracing_off and tracing_start()/tracing_stop
 *
 * Use tracing_on/tracing_off when you want to quickly turn on or off
 * tracing. It simply enables or disables the recording of the trace events.
 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
 * file, which gives a means for the kernel and userspace to interact.
 * Place a tracing_off() in the kernel where you want tracing to end.
 * From user space, examine the trace, and then echo 1 > tracing_on
 * to continue tracing.
 *
 * tracing_stop/tracing_start has slightly more overhead. It is used
 * by things like suspend to ram where disabling the recording of the
 * trace is not enough, but tracing must actually stop because things
 * like calling smp_processor_id() may crash the system.
 *
 * Most likely, you want to use tracing_on/tracing_off.
 */

enum ftrace_dump_mode {
    DUMP_NONE,
    DUMP_ALL,
    DUMP_ORIG,
};

static inline void tracing_start(void) {}
static inline void tracing_stop(void) {}
static inline void trace_dump_stack(int skip) {}

static inline void tracing_on(void) {}
static inline void tracing_off(void) {}
static inline int tracing_is_on(void) { return 0; }
static inline void tracing_snapshot(void) {}
static inline void tracing_snapshot_alloc(void) {}

static __printf(1, 0) inline int ftrace_vprintk(const char *fmt, va_list ap) { return 0; }
static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode){}

/* This counts to 12. Any more, it will return 13th argument. */
#define __COUNT_ARGS(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _n, X...) _n
#define COUNT_ARGS(X...) __COUNT_ARGS(, ##X, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0)

// #define __CONCAT(a, b) a##b
#define CONCATENATE(a, b) __CONCAT(a, b)

/* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
#ifdef CONFIG_FTRACE_MCOUNT_RECORD
#define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
#endif

/* Permissions on a sysfs file: you didn't miss the 0 prefix did you? */
#define VERIFY_OCTAL_PERMISSIONS(perms)                                                                \
    (BUILD_BUG_ON_ZERO((perms) < 0) +                                                                  \
     BUILD_BUG_ON_ZERO((perms) > 0777) + /* USER_READABLE >= GROUP_READABLE >= OTHER_READABLE */       \
     BUILD_BUG_ON_ZERO((((perms) >> 6) & 4) < (((perms) >> 3) & 4)) +                                  \
     BUILD_BUG_ON_ZERO((((perms) >> 3) & 4) < ((perms) & 4)) + /* USER_WRITABLE >= GROUP_WRITABLE */   \
     BUILD_BUG_ON_ZERO((((perms) >> 6) & 2) <                                                          \
                       (((perms) >> 3) & 2)) + /* OTHER_WRITABLE?  Generally considered a bad idea. */ \
     BUILD_BUG_ON_ZERO((perms) & 2) +                                                                  \
     (perms))
#endif
